Sword Hijacking is a trick that will allow you to hijack enemies in vehicles from a slightly greater distance in a map and at a faster speed under normal circumstances. It requires perfect timing, and an Energy Sword. This trick only works in Halo 2.
This technique is simple enough. Merely perform a Sword Cancel (by holding down the "X" button as you lunge) towards an enemy vehicle. Continue to hold down "X" while lunging, and you will automatically hijack the vehicle when you get near it. This is particularly useful for boarding enemy Scorpion Tanks, Wraiths, Banshees, and Ghosts. It is even more useful in multiplayer. If attempted in Halo 3, the trick will not work.